A method and circuit for measuring phase difference of fully electronic on-board transformer
By designing a phase difference measurement circuit for all electronic onboard transformers, the problem that the existing technology cannot accurately measure the phase difference of the onboard transformers is solved, and the precise measurement of the phase difference is achieved, which improves the yield rate of board and card production and the stability of product.
Patent Information
- Application Number
- CN202411876331.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-19
- Publication Date
- 2025-04-08
AI Technical Summary
The prior art cannot accurately measure the phase difference of onboard transformers, affecting the accuracy and yield of the fully electronic interlocking system.
A fully electronic onboard transformer phase difference measurement circuit is designed, and the phase difference between the primary and secondary voltages of the transformer is converted and calculated through primary and secondary sampling circuits, filter circuits, analog multipliers and AC signal amplitude detection circuits.
It realizes accurate measurement of the phase difference of the onboard transformer, improves the yield rate of board and card production, and provides important guarantees for the stable operation of the product.
Smart Images
Figure CN119780524A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to a method for measuring a transformer phase difference in the field of rail transit, and in particular relates to a method and a circuit for measuring a phase difference of a fully electronic onboard transformer. Background Art
[0002] With the continuous improvement of the degree of railway automation, the fully electronic interlocking system will be fully applied to the railway system. The various transformers originally used in the electrical centralized interlocking (track transformers, turnout indication transformers, etc.) will also be miniaturized and designed into the fully electronic circuit board. As the core components in various modules, the performance parameters of these transformers directly affect whether the fully electronic interlocking system can correctly collect turnout position information and track status information, etc., especially the transformers used in phase-sensitive track circuits, which have very high requirements on phase accuracy.
[0003] Currently, there is no corresponding method to measure the phase of the onboard transformer. The overall function of the board can only be tested after it is soldered to the circuit board, but it is impossible to accurately measure the phase of the transformer itself and the overall phase after combining with the corresponding resistor-capacitor circuit. Summary of the invention
[0004] The purpose of the present invention is to provide a method and circuit for measuring the phase difference of a fully electronic board-mounted transformer, so as to accurately measure the phase difference between the primary and secondary side voltages of the board-mounted transformer, thereby improving the yield rate during board production and providing important guarantee for the stable operation of the product.
[0005] The technical solution of the present invention is: it relates to a fully electronic on-board transformer phase difference measurement circuit, which is characterized in that it includes: an AC power supply that provides primary voltage to the transformer, a DC power supply that powers a digital circuit, a primary sampling circuit, a secondary sampling circuit, a filtering circuit, an analog multiplier, an AC signal amplitude detection circuit and a display device. The AC power supply provides voltage to the primary of the transformer, and the sampling circuit filters the primary and secondary voltages of the transformer through a filter and sends them to the input end of the analog multiplier. The output signal is sent to the AC signal amplitude detection circuit. The detection circuit has a 16-bit A / D processor, which converts the analog signal into a digital signal, and calculates and displays the primary and secondary phase differences by comparing the amplitudes of the positive and negative half-waves of the signal.
[0006] The frequency and voltage of the AC power supply are selected according to the actual application of the transformer.
[0007] The DC power supply uses a DC 5V power module.
[0008] The primary and secondary voltage sampling circuits are composed of two series resistors, and the principle of series resistor voltage division is adopted to obtain an AC signal with the same frequency and phase as the sampled voltage and an amplitude of 1V. In order to avoid the influence of the subsequent filtering circuit on the voltage collection, the current of the sampling resistor should not be less than 0.1A, and the accuracy of the resistor should not be greater than 0.5%.
[0009] The filtering circuit is mainly used to filter out the interference of the environment and surrounding devices, and prevent the interference from entering the analog multiplier.
[0010] The analog multiplier uses a high-precision four-quadrant analog multiplier to convert the primary and secondary signals of the transformer into an AC signal with twice the frequency and an amplitude that varies with the phase difference between the primary and secondary of the transformer; The AC signal amplitude detection circuit can use ADSP-21489 as a processor, filter the sampled data through an algorithm, then read the amplitude of the positive and negative half-waves of each cycle and sum them, then average the values of 5 cycles, and finally perform an inverse sine operation to obtain the phase difference between the primary and secondary signals of the transformer.
[0011] The advantages of the present invention are: by converting the phase difference between the primary and secondary voltages of the transformer into the difference between the positive and negative half-wave amplitudes of the AC signal, and finally accurately calculating and detecting the phase difference between the primary and secondary voltages of the transformer by detecting the difference between the positive and negative half-wave voltage peaks, the yield rate of the board production is improved, which provides an important guarantee for the stable operation of the product.
[0012] The present invention will be further described below in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 It is a circuit schematic diagram of the present invention; Figure 2 is a circuit schematic diagram of Embodiment 1 of the present invention; Figure 3 is a circuit schematic diagram of Embodiment 2 of the present invention; Figure 4 It is a schematic diagram of the AC signal amplitude detection circuit of Example 2.
[0014] In the figure: 1. AC power supply; 2. DC power supply; 3. Primary voltage sampling circuit; 4. Secondary voltage sampling circuit; 5. Filter; 6. Analog multiplier; 7. AC signal amplitude detection circuit; 8. Display device; 9. Reference power supply; 10. Rectification circuit; 11. Comparison circuit; 12. Amplification circuit.
[0015] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined purpose, the specific implementation methods, structural features and effects of the present invention are described in detail below in conjunction with the accompanying drawings and embodiments.
[0016] like Figure 1 As shown, the present invention relates to a phase difference measurement circuit for the primary and secondary sides of a fully electronic transformer, which is characterized by comprising: an AC power supply 1 for providing primary voltage to the transformer, a DC power supply 2 for powering a digital circuit, a primary sampling circuit 3, a secondary sampling circuit 4, a filtering circuit 5, an analog multiplier 6, an AC signal amplitude detection circuit 7 and a display 8. The AC power supply 1 provides voltage to the primary side of the transformer, and the primary and secondary voltages of the transformer are filtered by the primary sampling circuit 3 and the secondary sampling circuit 4 through the filter 5 and then sent to the input end of the analog multiplier 6. The signal output by the analog multiplier is sampled by the AC signal amplitude detection circuit 7, and the analog signal is converted into a digital signal. The phase difference between the primary and secondary is calculated by comparing the amplitudes of the positive and negative half-waves of the signal, and is displayed in the display 8 in digital form.
[0017] The present invention provides two embodiments for explaining the concept of the present invention. Example
[0018] like Figure 2 As shown, the present invention relates to a phase difference measurement method and circuit for the primary and secondary sides of a fully electronic transformer, which is characterized in that it includes: an AC power supply 1 for providing primary voltage to the transformer, a DC power supply 2 for powering a digital circuit, a primary sampling circuit 3, a secondary sampling circuit 4, a filtering circuit 5, an analog multiplier 6, an AC signal amplitude detection circuit 7 and a display 8. The AC power supply 1 provides voltage to the primary side of the transformer, and the primary and secondary voltages of the transformer are filtered by the primary sampling circuit 3 and the secondary sampling circuit 4 through the filter 5 and then sent to the input end of the analog multiplier 6. The signal output by the analog multiplier is sampled by the AC signal amplitude detection circuit 7, and the analog signal is converted into a digital signal. The phase difference between the primary and secondary is calculated by comparing the amplitudes of the positive and negative half-waves of the signal, and is displayed in the display 8 in digital form.
[0019] The AC signal amplitude detection circuit 7 is a processor, which is a processor with a 16-bit A / D, and ADSP-21489 can be used. First, the analog signal is sampled to convert it into a digital signal, and the sampled data is filtered and processed by an algorithm. Then, the amplitudes of the positive and negative half waves of each cycle are read and summed, and then the values of 5 cycles are averaged to obtain the final positive and negative half-wave amplitude difference. Finally, an inverse sine operation is performed to obtain the accurate phase difference between the primary and secondary signals of the transformer.
[0020] The frequency and voltage value of the AC power source 1 are selected according to the actual application of the transformer.
[0021] The DC power supply 2 uses a DC 5V power supply module.
[0022] The primary and secondary voltage sampling circuits are composed of two series resistors, and the principle of series resistor voltage division is adopted to obtain an AC signal with the same frequency and phase as the sampled voltage and an amplitude of 1V. In order to avoid the influence of the subsequent filtering circuit 5 on the voltage collection, the current of the sampling resistor should not be less than 0.1A, and the accuracy of the resistor should not be greater than 0.5%.
[0023] The filtering circuit 5 is mainly used to filter out interference from the environment and surrounding devices, and prevent interference from entering the analog multiplier 6.
[0024] The analog multiplier 6 uses MPY634U to convert the primary and secondary signals of the transformer into an AC signal with twice the frequency and an amplitude that varies with the phase difference between the primary and secondary of the transformer. Example
[0025] like Figure 3 As shown, the present invention relates to a method and circuit for measuring the phase difference between the primary side and the secondary side of a fully electronic transformer, which is characterized by comprising: an AC power supply 1 for providing a primary voltage to the transformer, a DC power supply 2 for powering a digital circuit, a primary sampling circuit 3, a secondary sampling circuit 4, a filtering circuit 5, an analog multiplier 6, an AC signal amplitude detection circuit 7 and a display light 8. The AC power supply 1 provides voltage to the primary side of the transformer, and the primary and secondary voltages of the transformer are filtered by the primary sampling circuit 3 and the secondary sampling circuit 4 through the filter 5 and then sent to the input end of the analog multiplier 6, and the output signal is sent to the AC signal amplitude detection circuit 7. The detection circuit compares with the reference source to detect whether the amplitudes of the positive and negative half-waves of the AC signal have reached the set threshold value. If so, the display light 8 is driven to light up, otherwise, the light is turned off, so as to judge whether the primary and secondary phase difference of the transformer is within the set range.
[0026] The frequency and voltage value of the AC power source 1 are selected according to the actual application of the transformer.
[0027] The DC power supply 2 uses a DC 5V power supply module.
[0028] The primary and secondary voltage sampling circuits are composed of two series resistors, and the principle of series resistor voltage division is adopted to obtain an AC signal with the same frequency and phase as the sampled voltage and an amplitude of 1V. In order to avoid the influence of the subsequent filtering circuit 5 on the voltage collection, the current of the sampling resistor should not be less than 0.1A, and the accuracy of the resistor should not be greater than 0.5%.
[0029] The filtering circuit 5 is mainly used to filter out interference from the environment and surrounding devices, and prevent interference from entering the analog multiplier 6.
[0030] The analog multiplier 6 uses a variable transconductance analog multiplier to convert the primary and secondary signals of the transformer into AC signals with twice the frequency and whose amplitude varies with the phase difference between the primary and secondary of the transformer.
[0031] like Figure 4 As shown, the AC signal amplitude detection circuit may include: a reference power supply 9, a rectifier circuit 10, a comparison circuit 11, and an amplifier circuit 12; the AC signal output by the analog multiplier 6 is rectified by the rectifier circuit 10 for positive half-wave and negative half-wave, and then compared with the reference power supply 9 by the comparison circuit 11 to detect whether the voltage amplitude reaches the set threshold value, and its output is a switching quantity, which is amplified by the amplifier circuit 12 to drive the display light 8. If the two display lights are on at the same time, it means that the amplitude of the AC signal meets the requirements, and then it is determined that the primary and secondary phase difference of the transformer is within the set value.
[0032] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.
Claims
1. A phase difference measurement circuit for the primary and secondary sides of a fully electronic on-board transformer, characterized in that it includes: An AC power source (1) for providing a primary voltage to a transformer, a DC power source (2) for powering a digital circuit, a primary sampling circuit (3), a secondary sampling circuit (4), a filtering circuit (5), an analog multiplier (6), an AC signal amplitude detection circuit (7) and a display (8); the AC power source (1) provides a voltage to the primary of the transformer, the primary sampling circuit (3) and the secondary sampling circuit (4) filter the primary and secondary voltages of the transformer through a filter (5) and then send them to the input end of the analog multiplier (6), the signal output by the analog multiplier (6) is processed by the AC signal amplitude detection circuit (7), the analog multiplier (6) converts the analog signal into a digital signal, and calculates the phase difference between the primary and secondary of the transformer by comparing the amplitudes of the positive and negative half-waves of the signal, which is displayed in a digital form on the display (8).
2. The phase difference measurement circuit of the primary side and the secondary side of the fully electronic on-board transformer according to claim 1 is characterized in that: The primary sampling circuit (3) and the secondary sampling circuit (4) are respectively composed of two series resistors, and the series resistors are used to divide the voltage to obtain an AC signal with the same frequency and phase as the sampled voltage and an amplitude of 1V.
3. The phase difference measurement circuit of the primary side and the secondary side of the fully electronic on-board transformer according to claim 2 is characterized in that: The current value passing through the sampling resistor should not be less than 0.1A, and the accuracy of the sampling resistor should not be greater than 0.5%.
4. The phase difference measurement circuit of the primary side and the secondary side of the fully electronic on-board transformer according to claim 1 is characterized in that: The DC power supply (2) uses a DC 5V power module.
5. The phase difference measurement circuit of the primary side and the secondary side of the fully electronic on-board transformer according to claim 1 is characterized in that: The filter circuit (5) comprises a primary coil filter circuit and a secondary coil filter circuit. The filter circuit (5) is used to filter out interference from the environment and surrounding devices, and prevent the interference from entering the analog multiplier (6).
6. The phase difference measurement circuit of the primary side and the secondary side of the fully electronic on-board transformer according to claim 1 is characterized in that: The analog multiplier (6) or MPY634U converts the signal between the primary and secondary of the transformer into an AC signal with twice the frequency and whose amplitude varies with the phase difference between the primary and secondary of the transformer.
7. The phase difference measurement circuit of the primary side and the secondary side of the fully electronic on-board transformer according to claim 1 is characterized in that: The analog multiplier (6) is a variable transconductance analog multiplier, which converts the signals of the primary and secondary of the transformer into AC signals with twice the frequency and whose amplitude varies with the phase difference between the primary and secondary of the transformer.
8. The phase difference measurement circuit of the primary side and the secondary side of the fully electronic on-board transformer according to claim 1 is characterized in that: The AC signal amplitude detection circuit (7) is a processor, which is a processor with a 16-bit A / D. The 16-bit A / D processor may adopt ADSP-21489. ADSP-21489 first samples and converts the analog model into a digital signal, filters the sampled data through an algorithm, then reads the amplitude of the positive and negative half-waves of each cycle and sums them, then averages the values of 5 cycles to obtain the final positive and negative half-wave amplitude difference, and finally performs an inverse sine operation to obtain the accurate phase difference value of the primary and secondary signals of the transformer.
9. The phase difference measurement circuit of the primary side and the secondary side of the fully electronic on-board transformer according to claim 1, characterized in that: The AC signal amplitude detection circuit (7) may include: a reference power supply (9), a rectifier circuit (10), a comparison circuit (11), and an amplifier circuit (12); the AC signal output by the analog multiplier is rectified into positive half-wave and negative half-wave by the rectifier circuit (10), and then compared with the reference power supply (9) by the comparison circuit (11) to detect whether the positive and negative voltages reach a set threshold value. The output is a switching quantity, which is amplified by the amplifier circuit (12) to drive the display light (8). The lighting of the display light reflects that the amplitude of the AC signal meets the requirements, thereby determining that the primary and secondary phase difference of the transformer is within the set value.
10. A method for measuring the phase difference between the primary side and the secondary side of a fully electronic on-board transformer, characterized in that: include: An AC power source (1) for providing a primary voltage to a transformer, a DC power source (2) for powering a digital circuit, a primary sampling circuit (3), a secondary sampling circuit (4), a filtering circuit (5), an analog multiplier (6), an AC signal amplitude detection circuit (7) and a display (8); the AC power source (1) provides a voltage to the primary of the transformer, the primary sampling circuit (3) and the secondary sampling circuit (4) filter the primary and secondary voltages of the transformer through a filter (5) and then send them to the input end of the analog multiplier (6), the signal output by the analog multiplier (6) is processed by the AC signal amplitude detection circuit (7), the analog multiplier (6) converts the analog signal into a digital signal, and calculates the phase difference between the primary and secondary of the transformer by comparing the amplitudes of the positive and negative half-waves of the signal, and displays it in digital form on the display (8); The phase difference between the primary and secondary voltages of the transformer is converted into the difference between the positive and negative half-wave amplitudes of the AC signal, and finally the difference between the positive and negative half-wave voltage peaks is detected to accurately calculate and detect the phase difference between the primary and secondary voltages of the transformer.